/Engine/Source/Developer/WidgetRegistration/Public/FToolkitWidgetStyle.h
[FToolkitWidgetStyle](API\Developer\WidgetRegistration\FToolkitWidgetStyle) & SetTitleBackgroundBrush ( const [FSlateBrush](API\Runtime\SlateCore\Styling\FSlateBrush) & InPaletteTitleBackgroundBrush )